“…Third, in the two‐way fixed effects models, we add unit‐specific linear time trends, which capture smooth changes in unobserved confounders. In practice, this corresponds to adding a third set of fixed effects for the interaction between the individual‐ and time variables, which ensures that potentially time‐varying confounding is controlled out (for applications in political science, see, e.g., Dinas et al., 2019; Jørgensen et al., 2022). While some controversy remains over whether to include unit trends, the concern is that it may constitute a conservative test by biasing coefficients towards zero (Goodman‐Bacon, 2021).…”